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Wyniki wyszukiwania dla: OPTIMIZATION METHODS.

OPTIMIZATION METHODS & SOFTWARE
Czasopisma 
Some Optimization Methods for Simulations in Volunteer and Grid Systems
PublikacjaIn this chapter, some optimization methods have been presented for improving performance of simulations in the volunteer and grid computing system called Comcute. Some issues related to the cloud computing can be solved by presented approaches as well as the Comcute platform can be used to simulate execution of expensive and energy consuming longterm tasks in the cloud environment. In particular, evolutionary algorithms as well...

Dimensionless Analysis of Stirling Engine using of Optimization Methods
PublikacjaW pracy zaprezetowano wyniki analizy wpływu parametrów konstrukcyjnych silnika Stirlinga na jego wskaźniki jakości.Analizę przeprowadzono na modelu bezwymiarowym wykorzystując metody optymalizacji parametrycznej.

Testing Stability of Digital Filters Using Optimization Methods with Phase Analysis
PublikacjaIn this paper, novel methods for the evaluation of digitalfilter stability are investigated. The methods are based on phase analysis of a complex function in the characteristic equation of a digital filter. It allows for evaluating stability when a characteristic equation is not based on a polynomial. The operation of these methods relies on sampling the unit circle on the complex plane and extracting the phase quadrant of a function...

Application of the Optimization Methods to the Search of Marine Propulsion Shafting Global Equilibrium in Running Condition
PublikacjaFull film hydrodynamic lubrication of marine propulsion shafting journal bearings in running condition is discussed. Considerable computational difficulties in nonlinear determining the quasistatic equilibrium of the shafting are highlighted. The approach using two optimization methods (the particle swarm method and the interior point method) in combination with the specially developed relaxation technique is proposed to overcome...

<title>Cavity control system: optimization methods for single cavity driving and envelope detection</title>
Publikacja 
Explicit SizeReductionOriented Design of a Compact Microstrip RatRace Coupler Using SurrogateBased Optimization Methods
PublikacjaIn this paper, an explicit size reduction of a compact ratrace coupler implemented in a microstrip technology is considered. The coupler circuit features a simple topology with a densely arranged layout that exploits a combination of high and lowimpedance transmission line sections. All relevant dimensions of the structure are simultaneously optimized in order to explicitly reduce the coupler size while maintaining equal power...

Prediction of protein structure using a knowledgebased offlattice unitedresidue force field and global optimization methods
Publikacja 
Selected multiobjective methods for multiperiod portfolio optimization by mixed integer programming
Publikacja 
Aeration Process in Bioreactors as the Main Energy Consumer in a Wastewater Treatment Plant. Review of Solutions and Methods of Process Optimization
PublikacjaDue to the key role of the biological decomposition process of organic compounds in wastewater treatment, a very important thing is appropriate aeration of activated sludge, because microorganisms have to be supplied with an appropriate amount of oxygen. Aeration is one of the most energyconsuming processes in the conventional activated sludge systems of wastewater treatment technology (may consume from 50% to 90% of electricity...

Optimization of Automata
PublikacjaThis book is conceived as an effort to gather all algorithms and methods developed by the author of the book that concern three aspects of optimization of automata: incrementality, hashing and compression. Some related algorithms and methods are given as well when they are needed to complete the picture.

MULTIOBJECTIVE OPTIMIZATION PROBLEM IN THE OptDMULTI METHOD
PublikacjaNew measurement technologies, e.g. Light Detection And Ranging (LiDAR), generate very large datasets. In many cases, it is reasonable to reduce the number of measuring points, but in such a way that the datasets after reduction satisfy specific optimization criteria. For this purpose the Optimum Dataset (OptD) method proposed in [1] and [2] can be applied. The OptD method with the use of several optimization criteria is called...

Complex multidisciplinary optimization of turbine blading systems
PublikacjaThe paper describes the methods and results of direct optimization of turbine blading systems using a software package Opti_turb. The final shape of the blading is obtained from minimizing the objective function, which is the total energy loss of the stage, including the leaving energy. The current values of the objective function are found from 3D RANS computations (from a code FlowER) of geometries changed during the process...

Ireneusz Czarnowski Prof.
OsobyIRENEUSZ CZARNOWSKI is a graduate of the Faculty of Electrical Engineering at Gdynia Maritime University. He gained a doctoral degree in the field of computer science at Poznan University of Technology and a postdoctoral degree in the field of computer science at Wroclaw University of Science and Technology. Since 1998 is associated with Gdynia Maritime University, currently is a professor of computer science in the Department...

Solar Photovoltaic Energy Optimization and Challenges
PublikacjaThe study paper focuses on solar energy optimization approaches, as well as the obstacles and concerns that come with them. This study discusses the most current advancements in solar power generation devices in order to provide a reference for decisionmakers in the field of solar plant construction throughout the world. These technologies are divided into three groups: photovoltaic, thermal, and hybrid (thermal/photovoltaic)....

Solar Photovoltaic Energy Optimization and Challenges
PublikacjaThe study paper focuses on solar energy optimization approaches, as well as the obstacles and concerns that come with them. This study discusses the most current advancements in solar power generation devices in order to provide a reference for decisionmakers in the field of solar plant construction throughout the world. These technologies are divided into three groups: photovoltaic, thermal, and hybrid (thermal/photovoltaic)....

Swarm Algorithms in Modern Engineering Optimization Problems
PublikacjaComplexity of today engineering problems is constantly increasing. Scientists no longer are facing issues, for which simple, mathematical programming methods are sufficient. Issues like autonomic vehicle navigation or classification are considered to be challenging, and although there exist valid means to solve them, in some cases there still is some place for improvement. With emergence of a new type of optimization techniques...

Parameters optimization in medicine supporting image recognition algorithms
PublikacjaIn this paper, a procedure of automatic set up of image recognition algorithms' parameters is proposed, for the purpose of reducing the time needed for algorithms' development. The procedure is presented on two medicine supporting algorithms, performing bleeding detection in endoscopic images. Since the algorithms contain multiple parameters which must be specified, empirical testing is usually required to optimise the algorithm's...

Small Antenna Design Using SurrogateBased Optimization
PublikacjaIn this work, design of small antennas using efficient numerical optimization is investigated. We exploit variablefidelity electromagnetic (EM) simulations and the adaptively adjusted design specifications (AADS) technique. Combination of these methods allows us to simultaneously adjust multiple geometry parameters of the antenna structure of interest in a computationally feasible manner, leading to substantial reduction of the...

Variablefidelity shape optimization of dualrotor wind turbines
PublikacjaPurpose Dualrotor wind turbines (DRWTs) are a novel type of wind turbines that can capture more power than their singlerotor counterparts. Because their surrounding flow fields are complex, evaluating a DRWT design requires accurate predictive simulations, which incur high computational costs. Currently, there does not exist a design optimization framework for DRWTs. Since the design optimization of DRWTs requires numerous model...

Optimization of Wireless Networks for Resilience to Adverse Weather Conditions
PublikacjaIn this chapter, we consider how adverse weather conditions such as rain or fog affect the performance of wireless networks, and how to optimize these networks so as to make them robust to these conditions. We first show how to analyze the weather conditions in order to make them useful for network optimization modelling. Using an example realistic network, we show how to optimize two types of wireless networks: freespace optical...

Applications of semidefinite optimization in quantum information protocols
PublikacjaThis work is concerned with the issue of applications of the semidefinite programming (SDP) in the field of quantum information sci ence. Our results of the analysis of certain quantum information protocols using this optimization technique are presented, and an implementation of a relevant numerical tool is introduced. The key method used is NPA discovered by Navascues et al. [Phys. Rev. Lett. 98, 010401 (2007)]. In chapter...

Optimization of Graphene Oxide Synthesis and Its Reduction
PublikacjaIn this article, we present the review of the chemical methods of synthesis of graphene oxide and its reduction in order to obtain the socalled reduced graphene oxide (rGO) whose properties are similar to those of pure graphene. We also present our experiments and the results in this field and the comparison of the efficiency of different methods of synthesis as well as the reduction of graphene oxide. To characterize the obtained...

Computationally Efficient Design Optimization of Compact Microwave and Antenna Structures
PublikacjaMiniaturization is one of the important concerns of contemporary wireless communication systems, especially regarding their passive microwave components, such as filters, couplers, power dividers, etc., as well as antennas. It is also very challenging, because adequate performance evaluation of such components requires fullwave electromagnetic (EM) simulation, which is computationally expensive. Although highfidelity EM analysis...

Expedited antenna optimization with numerical derivatives and gradient change tracking
PublikacjaDesign automation has been playing an increasing role in the development of novel antenna structures for various applications. One of its aspects is electromagnetic (EM)driven design closure, typically applied upon establishing the antenna topology, and aiming at adjustment of geometry parameters to boost the performance figures as much as possible. Parametric optimization is often realized using local methods given usually reasonable...

Multiobjective optimization of expensive electromagnetic simulation models
PublikacjaVast majority of practical engineering design problems require simultaneous handling of several criteria. For the sake of simplicity and through a priori preference articulation one can turn many design tasks into singleobjective problems that can be handled using conventional numerical optimization routines. However, in some situations, acquiring comprehensive knowledge about the system at hand, in particular, about possible...

Expedited EMDriven Design of Miniaturized Microwave Hybrid Couplers Using SurrogateBased Optimization
PublikacjaMiniaturization of microwave hybrid couplers is important for contemporary wireless communication engineering. Using standard computeraided design methods for development of compact structures is extremely challenging due to a general lack of computationally efficient and accurate simulation models. Poor accuracy of available equivalent circuits results from neglecting parasitic crosscouplings that greatly affect the performance...

Mariusz Kaczmarek dr hab. inż.
OsobyReceived M.Sc., Eng. in Electronics in 1995 from Gdansk University of Technology, Ph.D. in Medical Electronics in 2003 and habilitation in Biocybernetics and Biomedical Engineering in 2017. He was an investigator in about 13 projects receiving a number of awards, including four best papers, practical innovations (7 medals and awards) and also the Andronicos G. Kantsios Award and Siemens Award. Main research activities: the issues...

Model of the Internet mortgage market optimization
PublikacjaThe Internet mortgages are currently a fast growing market, allowing selling mortgages cheaper andfaster than in the traditional methods such as in bank departments.Given the specificity of selling mortgages in the Internet, banks try to sell more mortgages by spendingmore money on advertising and paying higher commission to the brokers selling their products. It is important tooptimise the amounts of money in both sectors (the...

A hybrid approach to optimization of radial inflow turbine with principal component analysis
PublikacjaEnergy conversion efficiency is one of the most important features of power systems as it greatly influences the economic balance. The efficiency can be increased in many ways. One of them is to optimize individual components of the power plant. In most Organic Rankine Cycle (ORC) systems the power is created in the turbine and these systems can benefit from effective turbine optimization. The paper presents the use of two kinds...

Mitigating the Energy Consumption and the Carbon Emission in the Building Structures by Optimization of the Construction Processes
PublikacjaFor decades, among other industries, the construction sector has accounted for high energy consumption and emissions. As the energy crisis and climate change have become a growing concern, mitigating energy usage is a significant issue. The operational and end of life phases are all included in the building life cycle stages. Although the operation stage accounts for more energy consumption with higher carbon emissions, the...

Lowcost multiobjective optimization and experimental validation of UWB MIMO antenna
PublikacjaPurpose–The purpose of this paper is to validate methodologies for expedited multiobjective designoptimization of complex antenna structures both numerically and experimentally.Design/methodology/approach–The task of identifying the best possible tradeoffs between theantenna size and its electrical performance is formulated as multiobjective optimization problem.Algorithmic frameworks are described for finding Paretooptimal...

Optimization of microstructure and properties of acceptordoped barium cerate
PublikacjaThe presented research concerns acceptor doped barium cerate and the attempts of improvement of its production method that would allow obtaining the solid electrolyte characterized by the particular properties. The authors suggest combining two production methods, molten salt synthesis and selfcombustion, in order to achieve the compound material that has some of the advantages of both of the initial methods. An impact of nickel...

Rapid design optimization of antennas using variablefidelity EM models and adjoint sensitivities
PublikacjaPurpose – Development of techniques for expedited design optimization of complex and numerically expensive electromagnetic (EM) simulation models of antenna structures validated both numerically and experimentally. The paper aims to discuss these issues. Design/methodology/approach – The optimization task is performed using a technique that combines gradient search with adjoint sensitivities, trust region framework, as well as...

Geometry optimization of steroid sulfatase inhibitors  the influence on the free binding energy with STS
PublikacjaIn the paper we review the application of two techniques (molecular mechanics and quantum mechanics) to study the influence of geometry optimization of the steroid sulfatase inhibitors on the values of descriptors coded their chemical structure and their free binding energy with the STS protein. We selected 22 STSinhibitors and compared their structures optimized with MM+, PM7 and DFT B3LYP/6–31++G* approaches considering separately...

Surrogate Modeling and Optimization Using ShapePreserving Response Prediction: A Review
PublikacjaComputer simulation models are ubiquitous in modern engineering design. In many cases, they are the only way to evaluate a given design with sufficient fidelity. Unfortunately, an added computational expense is associated with higher fidelity models. Moreover, the systems being considered are often highly nonlinear and may feature a large number of designable parameters. Therefore, it may be impractical to solve the design problem...

Spectrumbased modal parameters identification with Particle Swarm Optimization
PublikacjaThe paper presents the new method of the natural frequencies and damping identification based on the Artificial Intelligence (AI) Particle Swarm Optimization (PSO) algorithm. The identification is performed in the frequency domain. The algorithm performs two PSObased steps and introduces some modifications in order to achieve quick convergence and low estimation error of the identified parameters’ values for multimode systems....

Rapid multiobjective design optimization of miniaturized impedance transformer by Pareto front exploration
PublikacjaFast multiobjective optimization of compact impedance transformer is discussed. A set of alternative designs representing possible tradeoffs between conflicting design criteria, i.e., electrical performance (here, wideband matching) and the structure size, is obtained through Pareto front exploration by means of surrogateassisted methods.

Standard deviation as the optimization criterion in the OptD method and its influence on the generated DTM
PublikacjaReduction of the measurement dataset is one of the current issues related to constantly developing technologies that provide large datasets, eg. laser scanning. It could seems that presence and evolution of processors computer, increase of hard drive capacity etc. is the solution for development of such large datasets. And in fact it is, however, the “lighter” datasets are easier to work with. Additionally, reduced datasets can...

Tolerance Optimization of Antenna Structures by Means of Response Feature Surrogates
PublikacjaFabrication tolerances and other types of uncertainties, e.g., the lack of precise knowledge of material parameters, have detrimental effects on electrical and field performance of antenna systems. In the case of input characteristics these are particularly noticeable for narrow and multiband antennas where deviations of geometry parameters from their nominal values lead to frequency shifts of the operating frequency bands. Improving...

Fast Lowfidelity Wing Aerodynamics Model for SurrogateBased Shape Optimization
PublikacjaVariablefidelity optimization (VFO) can be efficient in terms of the computational cost when compared with traditional approaches, such as gradientbased methods with adjoint sensitivity information. In variablefidelity methods, the directoptimization of the expensive highfidelity model is replaced by iterative reoptimization of a physicsbased surrogate model, which is constructed from a corrected lowfidelity model. The success...

On deterministic procedures for lowcost multiobjective design optimization of miniaturized impedance matching transformers
PublikacjaPurpose This paper aims to investigate deterministic strategies for lowcost multiobjective design optimization of compact microwave structures, specifically, impedance matching transformers. The considered methods involve surrogate modeling techniques and variablefidelity electromagnetic (EM) simulations. In contrary to majority of conventional approaches, they do not rely on populationbased metaheuristics, which permit lowering...

Globalized parametric optimization of microwave components by means of response features and inverse metamodels
PublikacjaSimulationbased optimization of geometry parameters is an inherent and important stage of microwave design process. To ensure reliability, the optimization process is normally carried out using fullwave electromagnetic (EM) simulation tools, which entails significant computational overhead. This becomes a serious bottleneck especially if global search is required (e.g., design of miniaturized structures, dimension scaling over...

Generalized Formulation of Response Features for Reliable Optimization of Antenna Input Characteristics
PublikacjaElectromagnetic (EM)driven parameter adjustment has become imperative in the design of modern antennas. It is necessary because the initial designs rendered through topology evolution, parameter sweeping, or theoretical models, are often of poor quality and need to be improved to satisfy stringent performance requirements. Given multiple objectives, constraints, and a typically large number of geometry parameters, the design closure...

Optimization of Bread Production Using NeuroFuzzy Modelling
PublikacjaAutomation of food production is an actively researched domain. One of the areas, where automation is still not progressing significantly is bread making. The process still relies on expert knowledge regarding how to react to procedure changes depending on environmental conditions, quality of the ingredients, etc. In this paper, we propose an ANFISbased model for changing the mixer speed during the kneading process. Although the...

Pareto Ranking Bisection Algorithm for Expedited MultiObjective Optimization of Antenna Structures
PublikacjaThe purpose of this letter is introduction of a novel methodology for expedited multiobjective design of antenna structures. The key component of the presented approach is fast identification of the initial representation of the Pareto front (i.e., a set of design representing the best possible tradeoffs between conflicting objectives) using a Paretoranking bisection algorithm. The algorithm finds a discrete set of Paretooptimal...

Accelerated multiobjective design optimization of antennas by surrogate modeling and domain segmentation
PublikacjaMultiobjective optimization yields indispensable information about the best possible design tradeoffs of an antenna structure, yet it is challenging if fullwave electromagnetic (EM) analysis is utilized for performance evaluation. The latter is a necessity for majority of contemporary antennas as it is the only way of achieving acceptable modeling accuracy. In this paper, a procedure for accelerated multiobjective design of...

A MultiFidelity SurrogateModelAssisted Evolutionary Algorithm for Computationally Expensive Optimization Problems
PublikacjaIntegrating datadriven surrogate models and simulation models of different accuracies (or fidelities) in a single algorithm to address computationally expensive global optimization problems has recently attracted considerable attention. However, handling discrepancies between simulation models with multiple fidelities in global optimization is a major challenge. To address it, the two major contributions of this paper include:...

On ImprovedReliability Design Optimization of HighFrequency Structures Using Local Search Algorithms
PublikacjaThe role of numerical optimization has been continuously growing in the design of highfrequency structures, including microwave and antenna components. At the same time, accurate evaluation of electrical characteristics necessitates fullwave electromagnetic (EM) analysis, which is CPU intensive, especially for complex systems. As rigorous optimization routines involve repetitive EM simulations, the associated cost may be significant....

Computational intelligence methods in production management
PublikacjaThis chapter presents a survey of selected computational intelligence methods used in production management. This group of methods includes, among others, approaches based on the artificial neural networks, the evolutionary algorithms, the fuzzy logic systems and the particle swarm optimization mechanisms. From the abovementioned methods particularly noteworthy are the evolutionary and the particle swarm algorithms, which are successfully...